However, only three pitchers scored their 300th win between 1924 and 1982: Lefty Grove (1941), Warren Spahn (1961), and Early Wynn (1963). For Grove and Wynn it was the final win of their careers and each struggled in his last season to achieve it. This dearth of 300-game winners may be explained by the offensive explosion following the abolition of the spitball in 1921, changes in the ball itself, World War II military service (in the cases of Bob Feller and Red Ruffing), the growing importance of the home run in the game, and the lowering of the pitching mound following the 1968 season. As the home run became commonplace, the physical and mental demands on pitchers dramatically increased, leading to the use of a four-man starting rotation.
Then, in a mere eight years, between 1982 and 1990, the 300-win club gained six members — an increase of over 40%. This may be partly explained as a consequence of the era of free agency that began in the mid-1970s. Free agency led to unheard-of player salaries, which encouraged older pitchers to stay in the game longer than they might have in the past. Another part of the explanation is the increasing sophistication of training methods and sports medicine, which have allowed players to maintain a high competitive level for a longer time. A very good example of this is Phil Niekro, who was still under 200 wins at his 40th birthday, yet finished his career, at the age of 48, with 318 wins. Many of the pitchers who reached 300 wins in this era, such as Nolan Ryan, Don Sutton, and the aforementioned Niekro, had just a couple of 20+ win seasons and achieved the 300 mark by pitching well into their 40s (all 3 pitchers are in the Baseball Hall of Fame, however).
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| Pitcher | Wins | Date of 300th | Teams |
|---|---|---|---|
| 511 | July 3, 1901 | Cle (NL), Bos (AL), StL (NL), Bos (NL), Cle (AL), Bos (NL) | |
| 417 | May 14, 1920 | Was (AL) | |
| 373 | September 20, 1924 | Phi (NL), Chi (NL), StL (NL) | |
| 373 | June 28, 1912 | NY Giants (NL), Cin | |
| 363 | August 11, 1961 | Bos/Mil, NY Mets (NL), SF | |
| 361 | June 4, 1888 | Buf, Pit (Amer. Assoc.), Pit (NL), Pit (Players League), StL (NL) | |
| 361 | September 7, 1900 | Bos, StL, Phi (NL) | |
| 355 | August 7, 2004 | Chi (NL), Atl, Chi (NL), LA (NL), SD, LA (NL) | |
| 354 | June 13, 2003 | Bos, Tor, NY (AL), Hou (NL), NY (AL) | |
| 342 | June 4, 1890 | Troy, NY (Amer. Assoc.), NY Giants (NL), Phi | |
| 329 | September 23, 1983 | StL (NL), Phi, SF, Chi (AL), Cle, Min | |
| 328 | September 21, 1892 | Worc, Chi (NL), Bos (NL), Cle (NL) | |
| 326 | September 11, 1915 | Phi (AL), StL (Fed. League), StL (AL) | |
| 324 | July 31, 1990 | NY Mets (NL), Cal (AL), Hou (NL), Tex (AL) | |
| 324 | June 18, 1986 | LA (NL), Hou, Mil (AL), Oak, Cal | |
| 318 | October 6, 1985 | Mil/Atl (NL), NY (AL), Cle, Tor | |
| 314 | May 6, 1982 | SF, Cle, Tex, SD, NY (AL), Atl, Sea, KC | |
| 311 | August 4, 1985 | NY Mets (NL), Cin, Chi (AL), Bos | |
| 310 | May 14, 1891 | Prov, Bos (NL), Bos (Players League), Cin | |
| 307 | August 11, 1890 | Troy, NY Giants (NL) | |
| 305 | August 5, 2007 | Atl, NY Mets (NL), Atl | |
| 300 | July 25, 1941 | Phi (AL), Bos (AL) | |
| 300 | July 13, 1963 | Was, Cle, Chi (AL) |
Stats as of end of 2008 MLB season.
| Pitcher | Wins | Teams | Date of Birth |
|---|---|---|---|
| 295 | Mtl, Sea, Hou, Ari, NY (AL), Ari | 09/10/1963 | |
| 270 | Bal, NY (AL) | 12/08/1968 | |
| 246 | Chi (NL), Tex, StL, Bal, Bos, Sea, Phi | 11/18/1962 |